You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
81 lines
2.0 KiB
Python
81 lines
2.0 KiB
Python
3 years ago
|
"""Fit probability distributions to IPCC sea level rise forecasts.
|
||
|
|
||
|
|
||
|
Reads:
|
||
|
'IPCC AR6.xlsx'
|
||
|
|
||
|
Writes:
|
||
|
'png/*.png'
|
||
|
|
||
|
D. Howe
|
||
|
d.howe@wrl.unsw.edu.au
|
||
|
2022-05-12
|
||
|
"""
|
||
|
import os
|
||
|
import re
|
||
|
import numpy as np
|
||
|
import pandas as pd
|
||
|
from scipy import stats, optimize
|
||
|
import matplotlib.pyplot as plt
|
||
|
|
||
|
# Read data
|
||
|
df = pd.read_excel('IPCC AR6.xlsx', index_col=[0, 1, 2, 3, 4])
|
||
|
df = df.sort_index()
|
||
|
|
||
|
# Use all 'medium' confidence scenarios for intermediate quantiles
|
||
|
scenarios = ['ssp119', 'ssp126', 'ssp245', 'ssp370', 'ssp585']
|
||
|
dff = df.loc[838, 'total', 'medium', scenarios].groupby('quantile').mean()
|
||
|
|
||
|
# Use ssp119/ssp585 for 5th and 95th quantiles
|
||
|
dff.loc[5] = df.loc[838, 'total', 'medium', 'ssp119', 5]
|
||
|
dff.loc[95] = df.loc[838, 'total', 'medium', 'ssp585', 95]
|
||
|
dff = dff.T
|
||
|
|
||
|
dff.index.name = 'year'
|
||
|
percentiles = dff.columns.values / 100
|
||
|
values = dff.loc[2150].values
|
||
|
|
||
|
x_min = values.min() - 0.2
|
||
|
x_max = values.max() + 0.2
|
||
|
x = np.linspace(x_min, x_max, num=1000)
|
||
|
|
||
|
# Get statistical distributions
|
||
|
distributions = [
|
||
|
getattr(stats, d) for d in dir(stats)
|
||
|
if isinstance(getattr(stats, d), stats.rv_continuous)
|
||
|
]
|
||
|
|
||
|
for dist in distributions:
|
||
|
|
||
|
def cdf(x, loc, scale):
|
||
|
"""Calculate cumulative density function"""
|
||
|
return dist(loc=loc, scale=scale).cdf(x)
|
||
|
|
||
|
try:
|
||
|
loc, scale = optimize.curve_fit(cdf, values, percentiles)[0]
|
||
|
p = {'loc': loc, 'scale': scale}
|
||
|
|
||
|
except TypeError:
|
||
|
continue
|
||
|
|
||
|
fig, ax = plt.subplots(1, 2, figsize=(6, 2))
|
||
|
|
||
|
ax[0].plot(x, 100 * dist.cdf(x, **p))
|
||
|
ax[0].plot(values, 100 * percentiles, '.', c='#444444')
|
||
|
ax[1].plot(x, 100 * dist.pdf(x, **p))
|
||
|
|
||
|
ax[0].axhline(y=100, c='#000000', lw=0.8, zorder=-1)
|
||
|
ax[0].set_ylim(0, 101)
|
||
|
ax[1].set_ylim(bottom=0)
|
||
|
|
||
|
ax[0].set_title(dist.name, x=-0.7, y=0.5, ha='left')
|
||
|
|
||
|
for a in ax.ravel():
|
||
|
a.spines['right'].set_visible(False)
|
||
|
a.spines['top'].set_visible(False)
|
||
|
|
||
|
ax[1].set_yticks([])
|
||
|
|
||
|
plt.savefig(f'png/{dist.name}.png', bbox_inches='tight', dpi=100)
|
||
|
plt.close()
|